Sybase 12.4.2 Manuale Utente

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An overview of database permissions
354
 
DBA authority overview
When a database is created, a single usable user ID is created. This first user 
ID is 
DBA 
and the password is initially set to 
SQL
. The DBA user ID is 
automatically given DBA permissions, also called DBA authority, within the 
database. This level of permission enables the DBA user ID to carry out any 
activity in the database: create tables, change table structures, create new user 
IDs, revoke permissions from users, and so on.
Note  
To ensure database security, the DBA needs to change the password from 
the default of SQL to a new value.
Users with DBA 
authority
A user with DBA authority is referred to as the database administrator or 
database owner. In this chapter, frequent reference is made to the database 
administrator, or the DBA. This is shorthand for any user or users with DBA 
authority.
Although DBA authority may be granted or transferred to other user IDs, in 
this chapter it is assumed that the DBA user ID is the database administrator, 
and the abbreviation DBA is used interchangeably to mean both the DBA user 
ID and any user ID with DBA authority.
Adding new users
The DBA has the authority to add new users to the database. As users are 
added, they are also granted permissions to carry out tasks on the database. 
Some users may need to simply look at the database information using SQL 
queries, others may need to add information to the database, and others may 
need to modify the structure of the database itself. Although some of the 
responsibilities of the DBA may be handed over to other user IDs, the DBA is 
responsible for the overall management of the database by virtue of the DBA 
authority.
The DBA has authority to create database objects and assign ownership of 
these objects to other user IDs
 See the syntax of the commands for creating database objects, in “SQL 
Language Elements” in Adaptive Server IQ Reference Manual.
DBA user ID in case 
sensitive databases
User IDs and passwords are actually objects in the database. For this reason, if 
your database was created with the 
CASE RESPECT
 parameter, you must enter 
the user ID DBA and its default password SQL in uppercase. For case 
insensitive databases (the default), you can enter this user ID and password in 
either uppercase or lowercase.